I work for a manage service company and we have moved a lot of clients over to Office 365. Since doing so, many have been complaining that they are getting a lot of spam from people claiming to be a part of Microsoft or the Office 365 team. Is there any options, within O365 Admin Center, that can prevent these or severely reduce them? I know I can easily add the sender's address and domain to the spam block filter but this is starting to become problematic. Examples shown below:

In our experience, if receiving a message that passed
through the spam filters that and should be classified as junk or a phishing
scam, we could submit the message to Microsoft Spam Analysis or Microsoft
Phishing Analysis teams. The analysts will review the message and add it to the
service-wide filters if it meets the classification criteria.

To submit a junk or phishing scam message to Microsoft:

1. Create a blank email message.

2. Address the message to the Microsoft team that
reviews messages, as follows:

You could tweak O365 protection capabilities endlessly or do what many others are doing and put a secure email gateway (SEG) in front of it. Clearly SaaS is the best option. There are plenty of reviews around to help you identify who the players are. Cyren has been around for 15+ years providing protection technologies to other security players and a few years ago we moved into the SEG space. Take a look at our solution for O365. Around 40% of our current Cyren Cloud Security customers use us as well O365.